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Temperature rise on the electronic board can have a noticeable impact on the electronic circuit which result in some changes in the basic parameters of the circuit elements. The aim of this paper is to study and analyzes the effects of high temperature on the static and dynamic characteristics of a bipolar transistor. The research was carried out experimentally by studying and analyzing several parameters of the NPN BJT transistor type 2SC2120 at different temperatures. The obtained results showed that there is a significant increase in collector current from 0.19 A to 0.23 A and current gain from 0.14 to 0.22 by increasing the temperature from 25°C to 130°C. As for the threshold voltage, it was found that its value decreased from 0.6 volts to 0.4 volts. The results obtained also indicate that for the dynamic properties, the diffusion capacitance of the emitter-base junction, increased from 10.1 nF to 45.02 nF by increasing the temperature up to 130°C. Finally, it was found that the reverse capacitance of the gate-drain junction increased from 41.4 pF to 47.3 pF under the same temperature ranges.

The Marchica Lagoon stands as a one-of-a-kind ecosystem, hosting remarkable biodiversity and holding substantial tourism potential. It is the site of several major development projects aimed at exploiting its potential while ensuring its preservation and environmental sustainability. This paper examines the challenges of sustainable tourism in the Marchica lagoon, aiming to maximize economic benefits while minimizing negative environmental and socio-cultural impacts. In this study, we utilized a mixed-methods approach, which involved conducting quantitative surveys to collect data on lagoon ecosystem quality and qualitative analysis to investigate human interactions with the environment in-depth, followed by a comprehensive data analysis employing geostatistical techniques and thematic map analysis. Sustainable tourism in Marchica Lagoon has yielded significant results: an 80% preservation rate for its environment through eco-friendly practices, a remarkable waste recycling rate (70%), and an increase in visitor (60%) responsibility toward the lagoon's ecosystem. These achievements underscore the successful integration of environmental preservation and heightened awareness among tourists, making the region a model for sustainable tourism management. Embracing the Marchica Lagoon ecosystem involves fostering a harmonious relationship between environmental preservation, economic development, and local community satisfaction. Achieving this balance requires active collaboration among stakeholders and the diligent implementation of tailored environmental regulations, all working together to protect and sustain the delicate lagoon ecosystem.

Pulmonary embolism is one of the differential diagnoses of "acute chest" syndromes. We report a clinical case of contained rupture of ascending aortic aneurysm with pulmonary arteries compression, which was presented as pulmonary embolism, and we well review the literature data of this diagnostic trap.

We report the case of a cardiac papillary fibroelastoma of the aortic valve resected by simple shaving the pedicle. The macroscopic view showed a jelly-like aspect, with the classical appearance of a sea anemone under water, with multiple slender fronds and numerous little submillimetric thrombi disseminated among the branches of the tumor., (Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)